(1 中国能源建设集团湖南省电力设计院有限公司， 长沙 410007； 2 北京工业大学建筑工程学院，北京 100124； 3 中国电力科学研究院有限公司输变电工程研究所， 北京 102401； 4 国网西藏电力有限公司， 拉萨 850000)

摘要: 螺旋锚是一种施工高效、环保的基础，为支撑其在青藏高原架空输电工程中的应用，揭示碎石土地基螺旋锚基础抗拔承载机制，开展了不同安装角度、不同锚盘个数的单个螺旋锚基础轴向上拔，以及浅埋承台式螺旋锚群锚基础斜向上拔的原位载荷试验。 试验结果表明:单个螺旋锚基础竖向上拔荷载￣位移关系曲线介于陡降型与直线型之间，主要发生锚盘上部土体局部剪切破坏而进入承载极限状态，呈现深基础承载特性；螺旋锚竖向倾斜角度越大则其轴向抗拔极限承载力越小，但加载初期倾斜角度对承载性能的影响不明显，锚盘越多则承载力越大；浅埋承台式螺旋锚群锚基础在斜拉荷载作用下承台和螺旋锚均发挥了一定的抗拔和抗倾覆作用，其中竖向位移 20mm时浅埋承台因与地基相互作用而先期进入极限状态，随后主要由螺旋锚继续抵抗基础顶部增量荷载作用，另外群锚主要通过对承台的不均匀作用力来抵抗倾覆力矩。

关键词: 碎石土； 螺旋锚； 承台； 锚盘； 载荷试验； 承载机制

中图分类号:TU476. 9 文献标志码:A 文章编号:1002￣848X(2022)04￣0148￣05

DOI:10. 19701 / j.jzjg.LS201944

In situ loading test and bearing mechanism analysis of concrete cap type helical anchorfoundation for gravel soil ground in the Qinghai￣Tibetan Plateau

HUANG Yongxiang1， DING Shijun2，3， YUAN Xiaochao4， ZHAI Guoguang4， DING Mintao3

(1 China Energy Engineering Group Hunan Electric Power Design Institute Co.， Ltd.， Changsha 410007， China；2 College of Architecture and Civil Engineering， Beijing University of Technology， Beijing 100124， China；3 Institute of Transmission and Transformation Engineering， China Electric Power Research Institute， Beijing 102401，China； 4 State Grid Tibet Electric Power Co.， Ltd.， Lasa 850000， China)

Abstract:Helical anchor is a kind of high￣efficiency construction and environmental protection foundation. In order tosupport its application of the overhead power transmission project in the Qinghai￣Tibet Plateau， and to reveal the anti￣upliftbearing mechanism of the helical anchor foundation for gravel soil ground， the in￣situ loading tests of the single helicalanchor foundation with different installation angles and different number of anchor plates under the axial uplift loading， andthe shallow￣buried cap type helical anchor group foundation under the oblique uplift loading were carried out. The testresults show that the vertical uplift load￣displacement relationship curve of a single helical anchor foundation is between thesteep drop type and the straight type， and the local shear failure of the upper part of the anchor plate mainly occurs andenters the bearing limit state， showing the bearing characteristics of the deep foundation； The greater the vertical tilt angleof the helical anchor， the lower the ultimate axial uplift bearing capacity， but the inclination angle at the beginning ofloading has no obvious effect on the load￣bearing performance. The more anchor plates， the greater the bearing capacity.Under the oblique uplift loading， both the cap and the helical anchor of the shallow￣buried cap type helical anchor groupfoundation play a certain anti￣uplift and anti￣overturning effect. When the vertical displacement is 20mm， the shallow￣buried cap will initially enter the limit state due to the interaction with the ground， and then the helical anchor will continueto resist the load on the top of the foundation. In addition， the group anchors mainly resist the overturning moment by theuneven force on the cap.

Keywords:gravel soil； helical anchor； cap； anchor plate； loading test； bearing mechanism

第一作者:黄勇祥，硕士，正高级工程师，主要从事输电线路结构工程设计，Email:26778837@ qq.com。

[引用本文] 黄勇祥，丁士君，袁小超，等. 青藏高原碎石土地基混凝土承台式螺旋锚基础原位载荷试验及承载机制分析[J]. 建筑结构，2022，52( 4):148￣152，105. HUANG Yongxiang，DING Shijun，YUAN Xiaochao， et al. In situloading test and bearing mechanism analysis of concrete cap type helical anchor foundation for gravel soil ground in theQinghai￣Tibetan Plateau[J]. Building Structure，2022，52(4):148￣152，105.